Fibroin spinning solutions



Reissued June 12, 1945 omEDssm-s PATENT OFFICE FIBROIN SPINNING SOLUTIONS Rudolph S. Bley, Milligan College, Tenm, assignmto North American Rayon Corporation, New York, N. Y., a corporation of Delaware No Drawing. Original No. 2,145,855 dated Februany 7, 1939, Serial No. 59,912, January 20, 1936.

Renewed April 19, 1938.

Reissue No. 21,454,

dated May 211, 1940, Serial No. 262,234, March This application for reissue August 2 1940, Serial No. 349,983

20 Claims. (Ci. 106-141) The present invention rel:.;: -.s to a process of manufacturing solutions of proteins, such as fibroin, casein, gelatin, wool and alginic acid, from which the proteins may be precipitated by suitable reagents.

One object of this invention is to prepare a spinning solution containing a protein selected from the group consisting of silk fibroin, wool,

gelatin, alginic acid and casein from which artificial products, such as filaments, yarns, ribbons, films, etc., may be formed.

Another object of my invention has to do with the preparation of a spinning solution by dissolving fibroin in a quaternary benzyl substituted ammonium base.

A third object of my invention relates to the manufacture of fibroin spinning solutions by dissolving a fibroin, such as natural silk, in a quaternary benzyl substituted ammonium hydroxide.

A fourth object of this invention has to do with the preparation of a spinning solution containing cellulose or cellulose derivatives and fibroin from which these substances may be precipitated in hydrated form.

Other objects of my invention will become apparent to those skilled in the art from a study of the following specification.

I am well aware that processes are already known for dissolving silk fibroin in ammoniacal copper hydroxide, etc., to produce spinning solutions therefrom. However, such solutions have proven unstable due to degradation of the fibroin molecule, this degradation resulting in a decrease in viscosity of such fibroin solutions. In accordance with the present invention this degra{ dation of the fibroin molecule is substantially counteracted by dissolving natural silk in solutions of quaternary benzy1 substituted ammonium bases. I have found by experimentation that -fibroin may be rapidly and completely dissolved in high-molecular organic ammonium bases having the general structure in which R1, R2 and R3 represent alkyl, aryl and/or aralkyl groups or substituted derivatives thereof. In addition,I have found that benzyl substituted, quaternary ammonium hydroxides are especially suitable for dissolving fibroin, wool, etc., to form spinning solutions. Although I have found that trimethyl -'benzyl ammonium hydroxide is an excellent solvent for fibroin, wool, etc, other quaternary benzyl-ammonium hydroxides may be used'for this purpose, such as triethyl-benzyl-ammonium hydroxide, dimethylphenyl benzyl ammonium hydroxide, diethylphenyl benzyl ammonium hydroxide, dioutylphenylbenzyl ammonium hydroxide, di-

'methyl-tolyl-benzyl-ammonium hydroxide, di

- acid salts and the like. However, it is to methyl amyl benzyl ammonium hydroxide, dimethyl-dibenzyl-ammonium hydroxide, benzyl-pyridonium hydroxide, dibutyl-dibenzyl-ammon'lum hydroxide, tolyl-pyridonium hydroxide, etc. In other words, I may use any water-soluble his :.-molecular quarternary ammonium hydroxide which has a strong basic reactionand which is able to dissolve fibroin, wool, cellulose, etc, Benzyl substituted ammonium hydroxides are able to dissolve such substances in relatively short periods of time to form clear, filtrable solutions. The fibroin can be precipitated from such solutions by diluting them with water or by causing the ammonium base to react with es? noted that aqueous solutions of 1 benzl substituted ammonium hydroxide should be preferably of about to 50% strength, i. e., about 2 normal.

' tions. decomposition by the solvent by raising the tem- It is also preferable to dissolve fibroin in quaternary ammonium bases at an elevated temperaturev for the formation of clear filtrable solu- I-Iowever, care must be exercised to avoid perature too high. Although it has been found that such fibroin solutions keep well on standing at ordinary room temperature, the degradation of fibroin may be practically overcome by storing said solutions at a low temperature; The solutions may be diluted to some extent with water without causing precipitation of fibroin provided suitable emulsifying agents, such as trimethylbenzyl-ammoni'um oleate, alkali metal salts of fatty acids, etc., are added thereto in suitable proportions.

Any known type of delustering agent which is stable in quaternary ammonium bases, such as oils, pigments, dyestuffs, etc., may be dispersed by suitable means in these .fibroin solutions for the production of soft-lustre or colored products therefrom.

Instead of using a fibroin solution per se for the production of filaments, yarns, films, etc., I may form mixed spinning solutions containing for example flbroin and cellulose, since both substances maybe dissolved in quaternary ammonium hydroxides. For this purpose, Inlay dissolve for example natural silk and cellulose or a cellulose derivative, such as cellulose esters and others in a concentrated, aqueous solution of a trimethyl-benzyl and cellulose, etc.

benzyl substituted ammonium hydroxide such as ammonium hydroxide, etc. The fibroin-cellulose or fibroin-cellulose derivative solution may be subsequently spun into water, dilute acids or salt solutions to form filaments, yarns, ribbons or films. Solutions may also be spun containing fibroin, cellulose and a rubber latex. The solutions, set forth above, may A be spun in funnels like cuprammonium cellulose or they may be precipitated and coagulated like viscose in setting baths. The coagulated products may be collected on spools or in centrifugal pots. Cellulose sponges maybe formed in'molds in well-known manner. Any known delustering agent which is stable in quaternary benzyl substituted ammonium bases may be added in suitable amounts to fibroin, fibroin-cellulose, fibroincellulose derivative or fibroin-wool ,or mixtures thereof to modify the lustre and other physical characteristics of the finished products. The ammonium bases may be recovered from the setting baths by suitable means and re-employed for the dissolution of fibroin, cellulose, wool, etc., to render the process more economical.

Example I ting bath containing for example dilute sulphuric acid and sodium sulphate. The threads are collected on spools or in pots, washed and dried. Wool, gelatin, alginic acid or casein may be disrayon art may be used to modify the physical 1 properties .of products manufactured from my novel spinning solutions. Instead of completely dissolving the carbohydrates in benzyl substituted quaternary ammonium hydroxide, they maybe pretreated therewith and subsequently xanthated with carbon bisulphide to form solutions from which artificial silk may be spun.

I wish to emphasize that the substances, set forth within the scope of the appended claims.

I claim: 4 a 1. A spinning solution for the manufacture of artificial products comprisi'ng a protein selected from the group consisting of silk fibroin, wool,

gelatin, alginic acid and caselnfinely dispersed in a quaternary benzyl substituted ammonium base having the structure canon,

HO R1 in which R1, R2 and Rs represent a radical selected from the group consisting of alkyl radicals, aryl radicals,'aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity solved insimilar manner to form solutions which are spun like silk flbroin.

Example ll Natural silk and cellulose are dissolved together in a quaternary ammonium hydroxide, preferably trimethyl-benzyl ammonium hydroxide, and spun as set forth in Example I. Instead I of cellulose or regenerated cellulose, a cellulose derivative, 1. e., esters and ethers, may be dissolved together with fibroin. Instead of forming Example III Fibroin, wool, gelatin, alginic acid or casein solutions withor without cellulose additions are diluted with water after the addition of a suitable emulsifying agent, such as trimethyl-benzyl oleate to such extent that the solid phase is not precipitated, spun and after-treated in accordance with the methods set forth above.

Instead of feeding the spinning solutions, set

I forth above, singly to the spinning nozzles, I may extrude for example a fibroin solution together with a cellulose solution from a single or a plurality of spinnerettes and obtain composite prod--' ucts consisting'of natural silk and cellulosefilaments, etc. In this manner, I may also produce mixed products consisting of natural silk, wool Furthermore, I may admix pigments or other solid and liquid delustrants with my spinning solutions for the production of yarns composed of differently colored ,filaments, etc; present invention, any method known in the In other words, according to the I on standing for relative long periods of time at a temperature not excee ing ordinary room tem- D ratures.

2.- A spinning solution for the manufacture of artificial products comprising a casein finely dispersed in aquaternary benzyl-substituted ammonium base having the structure CIHICH: B1 7 in which R1, R2 and R3 represent a radical selected from the group consisting of alkyl radicals,

aryl radicals, aralkyl radicals, substituted *alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures. v

3. A spinning solution for the manufacture of artificial products comprising an alginic acid in which R1, R2 and R: represent a radical selected from the group consisting of alkyl radicals,

aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room I in a trimethyl-benzyl-ammonium hydroxide, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

5. A spinning solution for the manufacture of artificial products comprising a silk fibroin 'finely dispersed in a trimethyl-benzyl-ammonium hydroxide, said solution having the property ofsubstantially retaining its viscosity on standing for relatively long periods of time at a-temperature not exceeding ordinary room temperatures.

6. A spinning solution for the manufacture of artificial products comprising a casein finelydispersed in a trimethyl-benzyl-ammonium' hydroxide, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures."

7. A spinning solution for the manufacture of artificial products comprising an alginic acid finely dispersed in a trimethyl-benzyl-ammonium hydroxide, said solution having the property of retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

8. A spinning solution for the manufacture of artificial products comprising a protein selected from the group consisting of silk fibroin, wool.

gelatin, alginic acid and casein finely dispersed in a quaternary benzyl substituted ammonium base having the structure in which R1,, R: and a; represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl'radlcals and substituted aralkyl radicals together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having theproperty of substantially retaining its viscosity on standing for relatively long periods or time at a temperature not exceeding ordinary room temperatures.

9. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely dispersed in a quaternary benzyl substituted ammonium base having the structure in which R1, R: and R: represent a radical selected from the group consisting of alkyl radicals,

aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, together with a celluloslc substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary roomtemperature's.

10. A spinning solution for the manufacture of artificial products comprising a casein finely dispersed in a quaternary benzyl substituted amonium base having the structure -R| cimcn .\i

in which R1, R2 and R: represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standingfor relatively long periods of time at a temperature not .exceeding ordinary room temperatures. 7

11. A spinning solution for the manufacture of artificial products comprising an alglnic acid finely dispersed in a quarternary benzyl substituted ammonium base having the structure in which R1, R2 and R3 represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals, substituted alkyl rad- 'icals, substituted aryl radicals and substituted aralkyl radicals together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exseeding ordinary room temperatures.

12. A spinning solution for the manufacture of artificial products comprising a protein selected from the group consisting of silk fibroin, wool,

gelatin, alginic acid and casein finely dispersed in a trimethyl-benzyl-ammonium hydroxide together with a cellulosic substance selected from the group consisting of cellulose, cellulose esters and cellulose ethers, said s0l1iti0nhaving the property of substantially retaining its .viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures. f l

13. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely dispersed in a trimethyl-benzyl-ammonium hydroxide together with a cellulosic substance selected from the group consisting of cellulose, cellulose ethers and cellulose esters, said solution having the property of substantially retaining its viscosity on standing-for relatively long periods of time at a temperature not exceeding ordinary.

room temperatures.

14. A spinning solution for the manufacture of artificial products comprising a casein finely dispersed in a trimethyl-benzyl-amm'onium hydroxide together with a cellulosic substance selected from the group consisting of cellulose, cellulose ethers and cellulose esters, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures. I

15. A spinning solution for the manufacture of artificial products comprising an alginic acid finely dispersed in a trimethyl-benml-ammonium hydroxide together with a cellulosic substance selected from thegroup consisting ofcellulose, cellulose ethers and cellulose esters. said solution having the property of substantially retaining its viscosity onstanding for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

16. A spinning solution for the manufacture of artificial products comprising a silk flbroin finely dispersed in a quaternary benzyl substituted ammonium base having the structure 0.11.0 R. R1 /N 11: H O R:

in which R1, R2 and R3 represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals, substituted alkyi radicals, substituted aryl radicals and substituted aralkyl radicals, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

ceeding ordinary room temperatures.

17. A spinning solution for the manufacture of artificial products comprising a protein selected from the group consisting of silk fibroin, wool, gelatin, alginic acid and casein finely dispersed in a quaternary benzyl substituted ammonium base having the structure:

cimon, R1 :NgR-I no 11. in which R1, R: and Rs represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, and a'soap of a fatty acid, said solution having the property of substantially retaining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

18. Aspinning solution for the manufacture of artificial products comprising a casein finely dispersed in a quaternary benzyl substituted ammoniumbase having the structurez in which R1, R3 and R: represent a radical se- 19. A spinning solution for the manufacture of artificial products comprising a silk fibroin finely dispersed in a quaternary benzyl substituted ammonium base having the structure:

alkyl radicals, and a soap of a fatty acid, said solution having the property of substantially re- ,taining its viscosity on standing for relatively long periods of time at a temperature not exceeding ordinary room temperatures.

20. A spinning solution for the manufacture of artificial products comprising an alginic acid finely dispersed in a quaternary benzyl substituted ammonium base having the structure:

in which R1, R2 and R: represent a radical selected from the group consisting of alkyl radicals, aryl radicals, aralkyl radicals, substituted alkyl radicals, substituted aryl radicals and substituted aralkyl radicals, and a soap of a fatty acid, said 

